1. Field of the Invention
This application relates to an electrical connector employing a plurality of lanceless contacts having both a primary lock and a secondary lock and more particularly relates to a pin and socket electrical connector employing a hinged secondary lock.
2. Description of the Prior Art
Pin and socket connectors employing stamped and formed pin and socket contacts crimped to wires in position with an integrally molded plastic housings have been widely used in computers, business machines, home entertainment apparatus, vending machines, automobiles and other applications. Commercial pin and socket connectors of this type are suitable for assembly by initially crimping individual pin and socket terminals to insulated wires and then inserting a plurality of crimped terminals into integrally molded plastic housings having cavities extending therethrough. U.S. Pat. No. 4,443,048 discloses one such pin and socket electrical connector in which each of the pin and socket contacts has deflectable resilient lances extending outwardly from the periphery thereof.
Although pin and socket connectors having lanced contacts have been generally acceptable to the harness making industry, some problems have been noted because of plastic deformation of the lances, resulting in inadequate assurance that the contacts are retained within cavities in the housings. Problems have also arisen because the lances on the contacts can cause snagging of harness wires. Therefore, lanceless pin and socket contacts retained in the insulative housings by resilient plastic members have been employed. U.S. Pat. Nos. 4,544,220 and 4,708,662 disclose pin and socket electrical connectors having lanceless contacts. Each of these connectors employ at least a two piece housing in which a retainer having flexible plastic latches is inserted in the rear of the contacts. U.S. Pat. No. 3,937,545 discloses an electrical connector employing pin and socket contacts in which plastic latches are incorporated as part of the main body housing. Additional secondary locking members providing back-up to the resilient latches are inserted into the mating faces of connector housings after the contacts have been assembled in respective halves of the connector assembly. Lanceless pin and socket electrical connectors employing a separate retainer or secondary lock member are shown in U.S. Pat. No. 4,787,864. Each of these pin and socket connectors employing lanceless pin and socket contacts employs a resilient housing latch which is cantilevered from one end and employs a inwardly facing protrusion which engages a circumferential recess on the lanceless pin or socket terminal. The use of this inwardly facing protrusion engagable with a circumferential recess means that each of the pin or socket terminals can be inserted into a corresponding cavity within a housing without the necessity of angularly aligning the contact relative to the corresponding cavity.
U.S. Pat. No. 4,655,525 discloses a pin and socket connector in which the connector includes radially expandable arcuate wall sections of housing cavities These arcuate wall sections are outwardly expandable when a terminal is inserted into the appropriate cavity and are free to return to their normal position and grip a recess on the exterior of a cylindrical in or socket terminal. This connector also employs a separate retainer insert which is positioned between parallel rows of cavities and between juxtaposed deflectable arcuate wall sections.
U.S. Pat. Nos. 4,711,508 and 4,750,893 both disclose and electrical connector having a dual housing lock. A first housing latch comprises a resilient member that snaps into an opening in a terminal inserted into the housing and a second lock comprises a hinge member which snaps into engagement with another surface on the terminal. The two housing latching members act independently and are employed with a terminal which must be properly oriented relative to the housing before either of the two independent housing latches will engage the terminal to secure it in place in a housing cavity. Other hinged locking members on insulating housings are shown in U.S. Pat. Nos. 3,693,134, and 4,754,183, and 4,753,612. The device shown in U.S. Pat. 4,753,612 uses both a resilient housing latch and a hinged housing latch which act separately to engage a single terminal, thus providing redundant retention of the single terminal. U.S. Pat. No. 4,017,141 discloses an electrical connector using a pin or socket terminal having lances on the terminal itself to provide primary retention. Secondary retention is provided by a hinged housing member which snaps closed behind a pin or socket terminal inserted into a housing cavity. None of these prior art references, however, disclose an electrical connector employing a one piece housing used with lanceless pin and socket terminals in which the one piece housing includes a first resilient housing latch to engage the lanceless contact terminal and a secondary locking member in the form of a hinged member which engages the resilient housing latch in a closed position and in which the hinged secondary locking member can only be closed if the first resilient locking member is in the fully engaged position. Furthermore, none of these references disclose an electrical connector in which the hinged locking member provides back-up and support for the primary resilient housing locking member.